FIELD OF THE INVENTION
The invention relates to a central lubrication system for a rotary printing press and, more particularly, to a central lubrication system with a central supply of lubrication for individual lubrication points and with a pipeline system for feeding an oversupply of lubrication to the individual lubrication points, the excess lubrication being returned and tested for water content and, if water is present, the printing press being shut down.
For such presses, a multiplicity of bearing points, tooth meshings, cam transmissions and the like are in existence which are supplied with a required quantity of lubrication in accordance with an individual lubrication chart during the operation of the press. Through the targeted supply of the individual lubricant points, only a relatively small quantity of lubricating oil has to be fed to the moving parts. In this regard, the supply of lubricant is always slightly greater than the required amount, which may involve only a few drops of lubricating oil, depending upon the respective lubricating point. This relatively small amount of oversupply of oil then drips or flows from the individual lubricating points and is collected in oilways or oil grooves or in other oil flow collector vessels. When, however, rollers of the inking unit in specific units of rotary printing presses, for example, in printing units, can be provided, it is not possible to exclude the occurrence of leakage losses in coolant feed lines which are present. If water is used as the coolant, one cannot reliably exclude the possibility that a few drops of water will not leak out over a long operating period of the press. This water, in droplet form, gets into the outwardly flowing or dripping lubricating oil and is fed together therewith to the central oil container. The danger then arises that the oil in the supply container of the central lubrication system may become nonusable. In this case, the parts of the press to be lubricated by the supplied water-oil mixture during the operation of the press may become damaged. Heretofore, this could only be prevented reliably if, for example, in the oil collecting vessel, another smaller oil container is provided wherein a signal is released by a sensor if water is present in the supplied oil (note published German Patent Application DE 38 43 498 C1). This additional container was to be removed manually and emptied, however, when the presence of water was detected, the oil normally found above the water being thereby lost.